D,
The compression ring looks to have been broken into pieces like that due to "over expansion", this was most likely caused by overheating. And the changing of altitudes that you're describing, most likely causes the motor to lean out, thus causing the heat. Also this would explain the "stuck" scraper rings and the missing parts of your pistons. Did you find all the missing parts of your pistons, before they damaged the heads or the cylinder walls? Also, did the excessive heat due any damage(tempering) to any of the surrounding components?
If these type of changes in altitude are a norm. for your use, I suggest that you probably install a oil temp. gauge somewhere that you can see it. Other than re jetting for changes in altitude which would be best, the only other thing I can suggest you looking into would be adjusting the timing differently. Just keep in mind that the higher the temp., the more the everything expands, especially the rings. I know that all this crap has surly ruined your day! :bang: If I can help, just let me know. :2thumbs:
DOC

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I am mounting a oil temp pressure gauge on thats for sure. Any suggestions are helpful. Its killing me know my dog is at the vet sick. But atleast I am doing it myself with a Bro
Cost Beers so far 12 pack

D,
I'm a very sceptical of most peoples "true" abilities these days, and being able to do anything yourself, gives one a real piece of mind! Monitoring and reducing oil temp is good in most cases. But not reducing it so low to inhibit the oil from lubricating properly. Like in the northern areas. With the changes altitude of your normal use, it would probably be a real good investment. For the life of me I can't remember which ignition will let you adjust the timing with just the rotation of the "thumb" switch. Someone out here can interject it her for my dumb a*s. I would strongly suggest your speaking to someone at S&S regarding your riding conditions and any suggestion on that end. They have quite a bit of knowledge on different set ups or alterations than can satisfy your needs here. But please, do thoroughly check out everything else for any other type of damage, scratches, discoloration, ect... You didn't just burn up a few parts here. On an air cooled engine, you "Burned It All Down"! Sorry, hate to tell you that Brother!

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It is great I can ride it year round here but riding at 18 degrees then summer 110 degrees is rough on an engine but I didnt buy this Dog not to ride.
The elevation thing..... Guess I will find a happy medium

wouldn't the enrichener need to be left open at the lower altitudes? As Vegas said the PSI sounds like a good option as its simply adjusted externally. Also with the ignition what about the thunderheart? just lift off the seat and change the setting isn't it?

Dakotabos Does this engine have piston oilers? When you build a fire on top of the piston and oil temps rise you will see it on the bottom of the piston looks like cooked oil. Spray jets if you have them should show where the oil hits.I agree heat broke the rings but you have a good carbon patch on the crown of the piston.If you are concerned about damage to the crank bearings I have a can cutter I can send you to cut oil filter open to look for debre.PM me if you need it! DO you know if this engine has cast pistons?

Standard EFI has the same issues. And it is only as good as the tune that is put into it.

My bike just ate another set of rings. We found out that the dyno tune looked good until the oil got hot (above 230 degrees) then the bike went lean. The tech that dyno'd my bike is good. I don't think anybody could have found this combination for the perfect storm unless they tuned each cell. Then it would be wrong when the weather changed.

Of course this happened right in the middle of where I cruise. And I spend hours on the bike at this point when I go travelling.

So with only 1200 mile since the last rebuild they are rebuilding it again. This time with a thundermax controller instead of the race tuner/delphi ECM combo.

I hope the 4th time is the charm.

These issues are why I started coming here. To see if 117" engines were just cursed.

The problem is I ride at 4000 then up at 10,000 above sea level then at sea level out in San Diego. Wish I could change it on the fly

I think tonight I will dig deeper means I am waiting on Parts. I have to order them today just want to make sure I get the right pistons on order today. They are comming from Wisconson and I will order them 2 day air so should be here Friday.

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Thanks Hoat I will check them out. That would help A LOT. I know when I leave here it doesnt matter until you change 2500 feet but thats easy to do with the great mountain range here and then home to South Dakota is at 1300

D,
From what I can see in the pics. the wrist pin looks just a little scared (scratches), most likely from the piston heat transferring into the rod and affecting the lubrication abilities.
Just keep in mind when doing anything, like Vegas remarked, higher altitudes = less air, and less air = burning rich (fat). The reverse is as well true, lower altitudes = more air, and more air = burning (Lean)!
The piston in the pics. doesn't look too bad, as far as burning mix. But remember, this is "not" a race engine, you don't want it to burn too awfully hot & clean. Personally I would like to see mine looking a little darker (Richer/Fatter).
Bikes like to be a little (fat). (Fat) = added torque! And that's what you "feel" in the performance of the bike. HP is great, but you can only really feel it in the higher RPM ranges and only then "if one really know what you're feeling and looking for"!. But, if you don't have the proper combination of HP along with torque, you really won't have much. So in reality bikes that are tuned to run just a little richer, run just a little quicker (torque) and better.
Just to give you an idea in differences. When I was racing, we'd go to the east coast at one race. Lots of humidity= less air, OK, so we'd (Lean) it down some, right. Then we'd leave an go to Phoenix, Hot & Dry = more air, So we'd (Fatten) it up some, right. You wouldn't think that there's a tremendous amount in the altitude differences between High Point NC. (Elev. 1,007 Ft.) and Phoenix AZ. (Elev. 1,117 Ft.) Some yes, but not a lot. We'd have to richen up 2 (main) jet sizes, or we'd loose pistons after 1 run! So the air densidy plays a factor as well. Start being a little rich (Fat) to be safe! Then adjust the ratio.

Dakotabos. Click on this site go to pic 1 here are the oilers Im talking about does your engine have these spray jets? Getting the bike back together is top priority at this point! The pictures of your piston show me that the rings are carbon up and stuck. So i think this has been going on for some time.I can see carbon scoring on the liner and glaze. Correct me if wrong I also see the piston separated on the intake side.I still think you have a defective cast piston or the valve smacked the piston which I cant see if it did though causing that fracture. Hope all goes well on your rebuild 05chop in southern wyoming http://www.zodiac.nl/instructions/S&SSSW+Engine.pdf

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05CHOP
I will check that out tonight when I swing by to clean up the Gaskets. Thats some great info. I am working with S&S and Big Dog to see what they think. S&S even sent me my sheet for my engine. That was great of them. Shows all part # and size

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